NON-VOLATILE MEMORY DEVICE HAVING A FLOATING GATE AND METHODS OF FORMING THE SAME

摘要

A non-volatile memory device having a floating gate and a forming method thereof are provided to increase capacitance between a control gate electrode and a floating gate by increasing an overlay area between the control gate electrode and the floating gate in a limited area. An isolation layer(109a) is formed on a semiconductor substrate to define an active region. A floating gate(117a) of a cylinder type is disposed on the active region, including flat plate part and a wall part extended upward from the edge of the flat plate part. A tunnel insulation layer is interposed between the floating gate and the active region. A control gate electrode(123a) crosses the active region, covering at least a part of the inner and outer surfaces of the floating gate. A blocking insulation layer(121) is interposed between the control gate electrode and the floating gate. The floating gate includes a first outer surface adjacent to the active region and a second outer surface adjacent to the isolation layer, wherein the second outer surface is covered with the control gate electrode.